Sorry for the long post.
Thought I would start a discussion about oil supply for installation of an oil cooler and/or oil filter. I have some concerns about the usual way to route the oil from the engine.
I am building a mild 650 engine using a later 126 engine with the wasted spark ignition. I really want to install a proper spin-on oil filter. I just think the centrifugal oil filter is antiquated and will never filter oil like a proper oil filter can. I also happen to have an OEM Saab engine oil cooler from my 9000 that I would like to install also.
The original oil path has the oil pickup sending oil through machined passages in the front of the timing cover to the oil pump gears. Oil is pressurized and sent out the hollow shaft of the driven gear into the front of the camshaft where the oil pressure is regulated. It goes from here to the centrifugal oil "filter" and then through the crankshaft, etc.
Most modifications are through the front timing cover. The hollow shaft is plugged and the oil forced to go out through a machined hole in the front cover. Return is to the tapped hole (normally plugged) at the front of the engine case at the 2:00 position which dumps into the camshaft front bearing.
To me this means that the oil pressure is unregulated, especially at start. I have had off forum discussions with Tom (the hobbler) and he said he was told that you need to drill a 2.5mm hole in the oil pump shaft plug so that some oil is bled back to the camshaft/oil pump interface, and that it prevents high cold start oil pressure. Still, to me, this is a compromise.
I realize that lots of people have done this modification and your engines are not exploding. Just looking for some guidance and assurance.
So my options would appear to be:
-Do the modification as most people have done and make sure to drill a 2.5mm hole in the oil pump shaft plug.
-Do not make any modification to the oil pump/timing gear cover. Instead tap into the oil sump and install a separate small electric oil pump as used to scavenge oil from turbos in turbocharged engines. I am leaning toward this method. This is also what Damon500 did.

Damon500 said:

I have been experiencing excessive oil temperature issues in our summer with my Giardiniera and also decided to fit an oil cooler.
In my case I didn't want to add further obstructions into the oil circuit as the lubrication system is marginal in the flat engines and not that easy to upgrade.
My solution has been to use a VDO electric oil pump operated by a temperature switch or the oil pressure light and a cooler mounted under the rear seat.
The pump is mounted low to prime quickly and has a capacity of 160l per hour which should mean that it circulates the entire sump through the cooler within a minute.
I have setup the system to bypass from the sump and return into the oil pump inlet so the system is effectively fail safe. One other advantage with this system is that it still maintains full flow through the cooler at idle when oil pressure is normally at its lowest.
So far the system has worked well and maintains oil pressure at idle and speed even after sustained 100km/h travel in high 30 degree summer temperatures.

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Here is a link to that discussion:https://www.fiatforum.com/500-classic/428031-oil-cooler-mod-4.html
Only problem I see for me with Damon's oil pump choice is that it is only capable of 0.5 bar (7.2 psi) which is fine for an oil cooler, but is not enough pressure for an oil filter. However, there are other pumps out there that will do 20 psi.
John

" I really want to install a proper spin-on oil filter. I just think the centrifugal oil filter is antiquated and will never filter oil like a proper oil filter can."

I'm sure that the more filters the better so long as oil flow and pressure don't suffer, both factors that you are obviously aware of. But I have said previously that my research indicates that a centrifugal filter actually removes finer particles than any filter medium can do.
For certain, the oil in my 500 stays clear for significantly longer than it does in my modern car. I must admit though...that's a diesel.

With modern oil filters catching particulates at 10 microns they will be performing an excellent job of preventing wear.
The statement regarding oil colour must factor the fact that compression fuel (diesel) creates carbon
The new oil will be black after one drive!
Higher performance engines will benefit from better filtration

AndrewHarvey said:

The statement regarding oil colour must factor the fact that compression fuel (diesel) creates carbon

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That's true, but I did acknowledge my comment being tongue-in-cheek:
"I must admit though...that's a diesel."
I wouldn't say that there is any less reason for good filtration in an engine of lower performance. And regardless of how good modern filtration systems are my point is that the centrifugal filter as originally fitted seems to do much more than simply an adequate job as it stands.
It's just a point of view. I prefer minimal complexity being simple myself.
I understand that it is satisfying and enjoyable to "gild the lily", I'm just not sure that many of the possible modifications are strictly necessary, but I really enjoy reading about them and may nick some of the ideas myself one day.

Peter and I must be of a similar generation---we both believe in the 'K.I.S.S.' principal. The Fiat 500 engine was designed by Aurelio Lampredi, who also designed the Fiat twin-cam engine and various Ferrari engines---he knew what he was doing. The 500 engine was designed to be serviced by anybody ---back-street garage, farmer etc with the minimum of tools and required parts. It may not look it to 'modern' eyes, but the centrifugal filter is remarkably effective, to the point that it was used in the 600D engine, also very successfully. To use the Porsche (urgh!) adage---if it aint broke, don't repair it. By bringing in an electric pump to the equation, you are adding complication and more things to go wrong. With a purely mechanical system you can virtually guarantee--if the engine is running, the system is working.
My advice, for what it is worth, is this. Use the system that the vast majority of tuners use. Small modification to the camshaft, oil-pipe take off from the front of the timing-chain cover (and if you don't want to use the commercially available parts, any good fabricator can weld on a take-off in the appropriate place), return feed into the (2.00 o'clock position) on the crank-case, and a remote filter mount with a spin-off filter. You can also build an oil-cooler into this system, although unless you live in a very hot part of the world, this requirement is debatable FOR A ROAD CAR. The fitment of a bigger (and for most purposes, the 3-1/2 litre sump is ample) aluminium sump AND the remote oil-filter will suffice to keep an engine well within the required temperature range. Here endeth the lesson!

Whilst I agree with the sentiments above- it would be a boring world if we all viewed issues the same way.
I have always enjoyed creating a personalised classic - with some modern improvements to aid use
The 500 has turned into a re-imagination of a 500 rally car - that never existed .....how silly......but fun
It's guaranteed to put a smile on all but the grumpiest of faces
I didn't want standard - so it's now an extreme metamorphosis!

Counterpoint.
The 500 is early 1950's engineering (example: kingpin front suspension). It was definitely built to a price. A lot of the mechanical items on the engine were designed to hit a certain selling price. I think it is safe to say that Fiat did not design the car or engine to last a real long time. It was basic transportation for Italy and the rest of Europe, not unlike a Morris Mini or Hillman Imp.
I think the centrifugal oil filter is part of this. It is relatively efficient, is a low cost design, and was novel in 1950. However, as Andrew pointed out, a modern oil filter will remove extremely fine particles. I just do not believe that the centrifugal system can do that. I think that this engine does not have an oil filter (readily available at the time it was designed) specifically for cost reasons.
Also the debris centrifugally separated from the oil is not separated from the oil system. It is possible for small portions of the "cake" to break off and get into the engine. Maybe from some shock, etc. Debris captured by an oil filter cannot get back into the system.

It would be interesting to see an oil analysis of two stock engines, one with the centrifugal system and the other with an oil filter after "x" miles.

I think the electric pump concept has another advantage in that if the pump should fail, it would have no negative impact on the engine. The original oil circuit having been maintained. I do intend to use a 3.5L aluminum sump.

Just my thoughts! I enjoy these discussions, by the way. I respect all of your opinions.
John

Totally agree John, we are all entitled to our opinion, and whilst we agree to respect these differing opinions, this forum will continue to be what it is--one of the best. It is also interesting (if not at times fascinating) to read of peoples differing approaches to the 'up-dating of the humble 'cinquecento'. Just to throw another defence of the humble 'centrifugal oil-filter' into the ring, the 500 that I had the longest (JJJ 43D) had its engine changed at 97,000 only because I had built-up a quicker engine, not because of any wear factor. Finally, look at the results for any of the long (and I do mean LONG) rallies--Peking to Paris etc. and see which cars usually come out on top---it is the old-fashioned engineered cars, not the built/designed by a computer cars. And I wonder how long that bit of discussion can last!!

To add a little bit to what 'the hobbler' said above in post #5 .

Fiat also used the centrifugal on the early Fiat twin cam engines, in 1438cc guise but they also had a spin-on filter in addition. So 2 filters.. The centrifugal filter was dropped on later, larger capacity twin cam engines.

I can't remember if this spin-on oil filter was a by-pass type or full flow when used in conjunction with a centrifugal filter, maybe someone here knows.

Also Honda afaik always used centrifugal oil filters on their smaller (up to 350cc, maybe 450cc?) motorcycle engines which had roller bearing crankshafts fitted. When they brought out the 4 cylinder bikes, 1st the 750cc followed by the 500cc, they used a spin-on filter but no centrifugal filter. Was believed at the time that crankshafts with thinwall (shell) bearings needed the better filtration afforded by spin-on oil (paper element) filters whereas roller bearing cranks could do fine with just centrifugal filters.

I accept that cost and ease of maintenance (+weight and use of scarce materials!) would have been big factors back when the 500 etc was being designed. I just wish the same factors were given more importance nowadays.

Re:- using an oil-cooler. I'd only consider using one if I found it necessary after testing, probably necessary on turbocharged or very highly modified engines but unlikely on slightly modded ones. If it was needed on a standard engine, the manufacturer would have fitted one. Iirc oil needs to be at a certain minimum temperature to do it's job correctly, i.e. oil that is too cold is bad for the engine. There used to be oil thermostats? available with remote oil filter kits, which made the oil bypass the cooler if the oil temperature was too low.

Al.

"I think it is safe to say that Fiat did not design the car or engine to last a real long time."

Damn....they failed on that one then.

It intrigues me that the longevity of the engine is an issue for people.
As Tom says, properly maintained and used they go on for an annoyingly long time without wearing out in any case. (By the way Tom, I had to look up "K.I.S.S", but that is definitely my outlook on things mechanical).

On a cheeky note....I don't think many Fiat 500 owners even use their cars enough for engine wear ever to be an issue ...(ducks head and leaves quickly........)

A quote that I live by.
Why do you want to climb Everest? Because it's there.....

Everyone to their own ideas makes for a colourful world...,and some different 500's....

A quote that I invented:

"Q. Why do you not want to climb Everest? A. Because it's cold and dangerous and I much prefer this sunny beach."

Hi John,
I have been happy with the results of using the scavenge pump to cool the oil in my 500 Giardiniera. Having said that I have had no problems with 500 or 650 engines in a mild state of tune simply running 10w60 fully synthetic but the Giardiniera flat engine has a small capacity sump that can't be enlarged also the cooling and lubrication system is not as efficient- I have modified mine to 650cc and experienced low oil pressure issues combined with failure of main bearings at very low mileage.
Since fitting the oil cooler I have had no issues at all and have travelled around 6000km including long drives at 100-110km/h with 2 passengers in 38-40 degrees Celsius.
The VDO pump is a transmission cooler pump https://www.injectorsonline.com/au/vdo-oil-pump.html and I have fed the oil back into an area of the pump adjacent to the oil intake where there was a blanking plug so it is 'failsafe' if the pump was to fail it will have no effect on normal operation of the system.
I haven't seen this setup used elsewhere but I'm happy with the results- you might want to run a non return valve in the outlet on the vertical engine as it will probably leak out into the sump when not running- I have mounted my pump low down adjacent to the sump base so that is no issue and it primes quickly.
I personally don't think an external filter is necessary either- provided good quality oil is used and changed annually a well built and mildly tuned 500 engine will outlast most people's ownership of the vehicle. I own one 500 sedan mildly tuned with 650 barrels that has lasted over 25 years since last rebuild and is still in excellent condition, also another standard 650 which has endured significant abuse over 10 years of continuous use and over 120,000km without a rebuild- it now has slight blow by but the bottom end (which is what the oil filter primarily protects) shows no obvious signs of wear with good oil pressure and no unusual vibrations or rumbles characteristic of an imminent rebuild.
I have another friend who travelled over 350,000km in his 126 before it's first rebuild running on standard Castrol GTX mineral oil (which is nothing special) but changed regularly
In essence- don't worry, the original design is just fine unless you significantly modify it.
Regards, Damon

Hello All,

Some years ago when I was playing Diesel Mechanic I was looking after a couple of fairly large (38m) fishing boats. One of them has a Scania engine (maybe 250 - 300hp) that powered a generator which had both centrifugal and cartridge filters fitted. Whenever we did the oil changes there was always a healthy build up of carbon, and general crap in the centrifugal filter as well as the odd bit of magnetic material. We always used to cut open the spin on paper filter was it was always ridiculously clean.... so clean in fact that when we pulled it off the first time we tested it to make sure it was actually working!

By contrast, the other gen set they had on the boat was a 14 litre Cummins engine which had just bog standard paper filters. Over the same period, with similar run times, the Cummins filter always had lots of stuff caught up in it as you would normally expect.

They both had the same oil change interval, they both ran the same oil, and they sat either side of the main engine in the same engine room about 20 feet from each other.

Centrifugal filtration is very effective, but they have to be cleaned out thoroughly. I pulled one of my 500D engines apart only to find the previous owner had never cleaned it. It was full of metal, and there was a film of crap in the bottom of the sump. So much for the previous owner telling me "Yeah mate, she has a reconditioned engine!"

As far as fitting external filters, oil coolers and the like? Personally I am not going to fit them to mine, but they do work. At the very least, they can't cause any harm and I can certainly appreciate the engineering involved in fitting them.

My two cents
Chris

F123C said:

Re:- using an oil-cooler. I'd only consider using one if I found it necessary after testing, probably necessary on turbocharged or very highly modified engines but unlikely on slightly modded ones. If it was needed on a standard engine, the manufacturer would have fitted one. Iirc oil needs to be at a certain minimum temperature to do it's job correctly, i.e. oil that is too cold is bad for the engine. There used to be oil thermostats? available with remote oil filter kits, which made the oil bypass the cooler if the oil temperature was too low.
Al.

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Keep in mind that this car was designed originally for use as a city car. Also, remember that VW had an oil cooler on every air cooled Beetle engine. I do agree about the need to not over cool the oil. My remote oil filter has an oil thermostat attached for the oil cooler. I will be driving this car for extended periods of time at 50+ mph (85+kph) in areas where the temperature reaches 33+C.
John

I have a spin on filter, remote thermostat and cooler and intend to drive every where like I stole it.!!! Even if my ambient temperature is low I hope to have my hot engine running hot!
I have enjoyed many performance cars, and my 500 maybe tiny but it should hopefully still be a road rocket....I have researched and found some performance air-cooled oils that I will use once it's run in and setup properly.
My commute has changed from 130 miles of motorway to 25 miles of B roads - should be perfect for a 500 with a bit of poke.

Hi everyone, happy New Year in advance I'm new to 500's and the forum so please excuse me for what could be daft questions

I've bought a Nanni oil cooler / spin-on filter kit and it comes with no instructions. I appreciate these kits are for competent mechanics but some guidance would have been useful:bang:! So there are a load of things I can't nail down 100% after researching on the forum or on the web generally.

The first is the hollow shaft that needs to be plugged. Before I get the cover off how is this done? Is the hole in the shaft threaded or would that be too optimistic?!

Then does the plug need to be drilled with a 2.5mm hole, as there seems to be different opinions? What are the pros'n'cons to drilling?

Does the cover need machining down where the oil seal goes for a 500R 126 type engine?

Will the oil pressure switch still 'read' correctly after the installation?

What's the best place to mount the radiator for good cooling but where its not vulnerable to stone damage?

Are the unfinished hoses supplied with the kit adequate? They need to be secured with jubilee clips, double ear clips or something as there are no fitting at the ends. The connections where the hoses are pushed on are barbed to help the hoses from slipping off but it still worries me a bit as I don't think I've ever seen oil cooler pipes fitted with clips.

There's probably more but that's enough for now!

Cheers for all your help,
Viggers

Hi Viggers;
Which kit did you buy--if you can let me know the part number, I will go through all your questions one by one. either on the forum or direct.

I would change the barbed push on fittings for hydraulic quality versions and either make your own hoses or by some from your local hose manufacturer.
Mount either under near side rear suspension or in the engine bay